A former candidate in Egypt’s presidential election has been detained as part of investigations that he might have offended “public decency” by making a rude hand gesture to a citizen before arriving in a court house.

Khalid Ali was detained on Tuesday for questioning in relation to the case in which he apparently acted against irresponsibly when he was arriving in the court in Cairo on January 16 this year.

A judicial source confirmed Ali’s detention for questioning, saying he would remain under custody for 24 hours. The source said that the prominent human rights lawyer was being sued by a private citizen.

Ali ran in Egypt’s 2012 election and has suggested he would do again against President Abdel Fattah al-Sisi in votes slated for 2018.

The lawyer has also been one of vocal critics of an agreement between Sisi administration and Saudi Arabia in April 2016 to hand over sovereignty over two islands in the Red Sea to the kingdom.
Ali has challenged the authenticity of the photo which has been used to target him in the decency case.

Since taking office three years ago, Sisi has hardly tolerated dissent as tens of thousands remain behind bars on alleged suspicion of having links to terror organizations.

Many of those targeted in the crackdown are members or followers of the Muslim Brotherhood, Egypt’s oldest and most established political party. Sisi, Egypt’s former army chief, took power after leading a military coup in 2013 against Mohammed Morsi, a key Brotherhood figure who won the country’s sole democratically-held elections five years ago.